1. Technical Field
The disclosure relates to a capsule medical device guidance system for guiding a capsule medical device that is introduced into a subject.
2. Related Art
Conventionally, capsule medical devices which are introduced into a subject to acquire various types of information on the inside of the subject or deliver a medicine or the like into the subject have been developed. As an example, a capsule endoscope which is formed in such a size that can be introduced into the gastrointestinal tract of a subject is known.
A capsule endoscope is a device which has an imaging function and a wireless communication function inside a capsule-shaped casing. The capsule endoscope acquires image data by capturing of an image (hereinafter referred to as an in-vivo image) of the inside of an organ of a subject while moving through the gastrointestinal tract by the peristaltic movement or the like after being swallowed into the subject and wirelessly transmits the image data sequentially. The wirelessly transmitted image data is received by a receiving device provided outside the subject, imported to an image display device of a workstation or the like, and subjected to prescribed image processing. In this way, the in-vivo image of the subject can be displayed as a still-image or a video image.
In recent years, a guidance system that guides a capsule endoscope introduced into a subject using a magnetic field has been proposed. This guidance system is configured such that a user can operate guidance of a capsule endoscope using an operation input device while referring to an in-vivo image based on the image data wirelessly transmitted from the capsule endoscope.
For example, JP 2009-66033 A discloses a capsule guidance system including a capsule endoscope which has an imaging element that captures an in-vivo image of a subject and a magnet having a magnetization direction relatively fixed with respect to the imaging element, a magnetic guidance device that applies a magnetic field to the magnet to guide the capsule endoscope according to a magnetic force, and a display unit that displays the in-vivo image acquired by the imaging element included in the capsule endoscope. In JP 2009-66033 A, when the magnetic guidance device is controlled to apply a magnetic field of a reference direction to the magnet in the capsule endoscope, and the magnet is magnetized in the reference direction following the magnetic field of the reference direction, a rotation angle of an image captured by the imaging element is initialized, the rotation of subsequent in-vivo images is corrected based on the image, and the in-vivo images of which the rotation is corrected are sequentially displayed on the display unit.
Moreover, JP 2004-255174 A discloses a capsule medical device guidance system including a capsule body in which a spiral projection is formed on an outer circumferential surface and a magnet is provided therein and a rotating magnetic field generator disposed outside a subject. In JP 2004-255174 A, when an operation instruction is input to the system, the rotating magnetic field generator generates a rotating magnetic field of the instructed direction and stores information such as the direction or the like of the rotating magnetic field. When an operation or the like of changing a moving direction of the capsule body is input, the moving direction of the capsule body is changed by continuously changing the state of the rotating magnetic field based on the stored information.